Change old surfacemap inputs to gridmap
Some brushes of mypaint-brushes package have wrong inputs.
This fixes that for Debian similarly as already done on MSYS2 https://github.com/msys2/MINGW-packages/commit/02162fe0e1f382baac12ee96c25e61f9aef5ff55 and macports https://github.com/macports/macports-ports/commit/3bcb9da45c4867032aa8f343094398e4c324677b